To the people that don’t believe it will spool, you must first understand the reasons why the 80 mm silver bullet is necessary and how it came about.
What follows is the simple secret to big power, with relative reliability. Well don’t listen.
First for maximum effort power you need lots of cool air. Air is the only limiting factor in any performance engine, including the Cummins diesel.
Another critical factor is air charge density, and to this end a cool intake charge is optimal.
The bottom line is pounds of air in the combustion chamber and not pounds of boost.
Twins are not the optimal selection to absolute maximum power. Twins are restrictive and work the air hard with two compressors producing a lot of heat .
They work great on multi purpose trucks, but if its all out power a proper sized single is the best selection
Now before you go defending street twins, I am talking about a maximum effert CR engine. If you make big boost numbers with twins you make heat. This heat translates in to high temperatures going in to the combustion chambers. You will still make power, but the thermal load on top of the piston is higher. When starting with higher combustion temperatures, it leads to component failures, remember any internal combustion engine works off thermal gas expansion. If you start with a higher temperature you will have to generate even more heat in the combustion process to develop the combustion chamber pressure at 10degrees ATDC to expand the air to push the piston down.
You can reduce compression ratio and fix the longevity problem, but by doing this you lose expansion efficiently.
This is why we are at this point in turbo development.
First cylinder head development has taken off with the inclusion of mainstream airflow development such as the work Chris Franks of ProStock cylinder head fame that now grinds for RayMac racing engines. is doing Before the last few years and, really not until one of Chris’s works of art found its way on to a CR in Project X, diesel head development was in the dark ages. John Russin developed and stills dose some really great heads, but only a few took advantage.
With these new heads, and some nifty cam technology the potential air flow of a B series doubled. Project X had a full array of data logger, and with this capability we found that these cutting edge engines needed a lot more air a lot more air.
A silver bullet 66 turbo that easily made big boost numbers making cool air was at its limit. With only 38 lbs of boost it did make 860+ hp, but the engine wanted more air. I have been providing data logger downloads to Brady and Shane for quite some time. The worked with me on my former ride and we worked steadily from one exhaust housing to a looser ones, each time making more power. That truck also makes over 1200 hp with only 35 to 38 lbs of boost.
So in a simple form
Better air flow = lower boost to make power,
Lower boost means you don’t have to make a turbo spool as far up
Bigger turbos means more air which = even more power
Attention: TDR Forum Junkies 
